1. Field of the Invention
The present invention relates to an electrical connector for electrically connecting a central processing unit (CPU) to a printed circuit board (PCB), more particularly relates to an electrical connector incorporated with metallic shields to avoid electromagnetic interference (EMI) for the CPU.
2. Description of Related Art
A conventional electrical connector for electrically connecting a central processing unit (CPU) with a plurality of conductive pins to a printed circuit board (PCB) disclosed in U.S. Pat. No. 6,340,309 which is issued to Lin et al. on Jan. 22, 2002 comprises a base having a plurality of terminals received therein, a cover mounted on the base and a driving member driving the cover sliding along the base. The base defines a first opening located at a middle position thereof and a plurality of passageways disposed around the first opening for receiving the terminals. The cover has a second opening corresponding to the first opening of the base and a plurality of through holes for the conductive pins of the CPU passing through. A hollow area is formed by the first and second openings. The electrical connector establishes electrical connection between the CPU and the PCB through the terminals contacting with the conductive pins of the CPU and the terminals being soldered to PCB.
As high-speed input/output and miniaturization requirements, the CPU is required to increase a plurality of electronic components disposed thereunder. The electronic components are received to the hollow area of the electrical connector when the CPU is assembled to the electrical connector. However, electrical signals occurred within the electronic components can produce electromagnetic interference (EMI) affecting electronic signal transmission of the terminals of the electrical connector.
To solve the problem that above mentioned, U.S. publication No. 2012/0045908A1 published to Chang (hereinafter “Chang”) on Feb. 23, 2012 discloses an electrical connector for electrically connecting a CPU with a plurality of electronic components assembled thereunder and conductive pins surrounding the electronic components to a PCB. The electrical connecter comprises a base having a plurality of terminals received therein for contacting with the conductive pins of the CPU, a cover mounted on the base, an actuator actuating the cover sliding along the base and a shielding frame mounted on the base. The base has a first opening and a plurality of passageways surrounding the first opening for receiving the terminals. The cover has a second opening corresponding to the first opening. The shielding frame is tightly attached to the sidewalls of the first opening and received in the first and second openings to prevent terminals from EMI emitted from electronic components assembled under the CPU.
As Chang discloses the single shielding frame tightly attached to the base, so when the cover moves relative to the base while the cover will move relative to the single shielding frame. When the CPU is mounted on the cover and moved with the cover, the CPU will move relatively to the shielding frame. Thus, a rigidity friction will generate between the CPU and the shielding frame that will damage the CPU.
Hence, it is desirable to provide an improved electrical connector to overcome the aforementioned disadvantages.